2006 – Donald H. Levy

Supersonic Jet Spectroscopy: From Diatomics to Biological Molecules

Using traditional techniques, it is difficult to observe and analyze the high-resolution gas-phase spectra of any but the smallest molecules: diatomics, triatomics, and somewhat larger molecules which have some symmetry to aid the analysis. Supersonic jet spectroscopy is a technique which greatly simplifies a molecule's gas-phase spectrum and extends the range of gas-phase spectroscopy to much larger species. In the lecture I will describe the technique and try to explain why it does what it does: i.e. why a supersonic jet expansion produces well-resolved spectra of large molecules. I will illustrate the lecture with examples of van der Waals molecules and molecules of biological interest which are usually not observed at all in the gas phase.